Ransomware Research

NM4 Ransomware

NM4 is a malicious ransomware strain that encrypts victim files and demands ransom payment for decryption. First observed in the wild on April 1, 2017, this ransomware has been actively targeting systems worldwide. Security researchers also track this malware under the aliases: NMoreira4.

Quick Facts

Ransomware Family
NM4
First Seen
April 1, 2017
Known Aliases
NMoreira4

How NM4 Ransomware Works

File Encryption Patterns

NM4 modifies encrypted files using specific patterns to mark them as encrypted:

File extensions added after encryption:

..NM4..NMCRYPT..NMoreira

Ransom Note and Payment Demands

After encrypting files, NM4 displays ransom notes demanding payment for file recovery:

fileRecovers your files.html

Ransom message:

notes/Recovers your files.html

Note locations:

EveryFolder
fileYOUR_DRIVE_HAS_BEEN_ENCRYPTED.TXT

Ransom message:

notes/YOUR_DRIVE_HAS_BEEN_ENCRYPTED.TXT

Note locations:

RootDiscs

Technical Indicators

Associated Executable Files

The following executable files are associated with NM4 ransomware:

  • 12.exe
  • file.exe
  • R NM4 NMoreira 4 ransomware
  • svchost.exe
  • scvhost.exe
  • out.exe
  • finish_work.exe

Elastio Can Help You

Don't let NM4 ransomware take over your data

Elastio provides advanced ransomware protection and recovery solutions to keep your organization safe.

Learn MoreRequest a Demo

About This Analysis

This NM4 ransomware analysis is part of Elastio's comprehensive ransomware detection database. Elastio provides advanced ransomware protection and recovery solutions, helping organizations defend against and recover from ransomware attacks like NM4.

Last updated: July 30, 2025

Recent Ransomware

Explore other threats in our database

View all ransomware